Basically substituted 1(2h)-phthalazinone derivatives

ABSTRACT

1. BASICALLY SUBSTITUTED 1(2H)-PHTHALAZINONE DERIVATIVE HAVING THE STRUCTURAL FORMULA   1-(O=),2-((R3)M-PHENYLENE-COO-CH(-CH2-R&#39;&#39;)-CH2-),4-R2,   (R1)N-1,2-DIHYDRO-PHTHALAZINE   AND THEIR PHARMACEUTICALLY ACCEPTABLE ACID ADDITION SALTS, WHEREIN R&#39;&#39; STANDS FOR A SUBSTUTUENT HAVING 2-10 CARBON ATOMS REPRESENTED BY THE FORMULA -NR4R5, WHEREIN R4 IS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, ALKYL AND BENZYL, AND R5 IS SELECTED FROM THE GROUP CONSISTING OF ALKYL, ALKENYL, HYDROXYALKYL, ALKOXYALKYL, DIALKYLAMINOALKYL, CYCLOALKYL, BENZYL AND PHENETHYL, R1 STANDS FOR A MEMBER SELECTED FROM THE GROUP CONSISTING OF A HYDROGEN ATOM AND AN ALKOXY GROUP HAVING 1-4 CARBON ATOMS, WHICH GROUP MAY BE IN THE 6,7 7,8 OR 5,6,7 POSITION OF THE PHTHALAZINE NUCLEUS, R2 STANDS FOR A MEMBER SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, METHYL AND BENZYL, R3 STANDS FOR AN ALKOXY GROUP HAVING 1-4 CARBON ATOMS, M STANDS FOR AN INTEGER SELECTED FROM THE GROUP CONSISTING OF 1,2 AND 3, AND N STANDS FOR AN INTEGER SELECTED FROM THE GROUP CONSISTING OF 2 AND 3.

US. Cl. 260-250 P 6 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to new pharmacologically valuable basically substituted l(2H)-phthalazinone derivatives having excellent coronary dilator properties and which have the general formula and their pharmaceutically acceptable acid addition salts, wherein R' stands for a radical selected from the group consisting of secondary aliphatic, Cycloaliphatic and araliphatic amines having 2 to 10 carbon atoms and 5,6 or 7-membered heterocyclic nitrogen bases, which contain in addition to the nitrogen atom a corresponding number of methylene groups as well as, optionally, an additional member selected from the group consisting of a nitrogen, an oxygen and a sulfur atom, said radical being bound via a nitrogen atom,

R stands for a member selected from the group consisting of a hydrogen atom and an alkoxy radical having 1 to 4 carbon atoms, which radical may be in the 6,7, 7,8 or 5,6,7 position of the phthalazine nucleus,

R is a member selected from the group consisting of hydrogen, alkyl and aralkyl,

R stands for alkoxy groups having 1 to 4 carbon atoms m is an integer selected from 1,2 and 3 and n is an integer selected from 2 and 3; and to processes for producing said derivatives.

The present invention relates to new, pharmacologically valuable, basically substituted 1(2H)-phthalazinone derivatives having the general formula United States Patent 3,845,052 Patented Oct. 29, 1974 and their pharmaceutically acceptable acid salts, wherein R stands for a secondary aliphatic, cycloaliphatic or araliphatic amine radical having 2 to 10 carbon atoms or the radical of a 5, 6 or 7-membered saturated heterocyclic amine, optionally containing an additional N, O or S hetero atom,

R represents hydrogen or an alkoxy group having 1 to 4 carbon atoms,

R represents hydrogen or an alkyl or aralkyl group,

R represents an alkoxy group having 1 to 4 carbon atoms,

mis1,2or3and n is 2 or 3, the groups R being attached if present to the phthalazine nucleus in the 6 and 7, 7 and 8 or 5, 6 and 7 positions.

The secondary amine radical R may be derived from an aliphatic monoor diamine, such as a dialkylamine, alkylalkenylarnine, alkylenediamine, hydroxyalkylamine or alkoxyalkylamine.

Suitable amines are for instance: dimethylamine, diethylamine, N-allyl-N-methylamine, N,N-diethyl N methylethylenediamine, N,N-diethyl-N'-methylpropylenediaminc. N-methylethanolamine, N-methylpropanolamine, N- isopropylethanolamine, N-butylethanolamine, N-benzylethanolamine, N-methyl N-( y-methoxypropybamine or N-methyl-N- ('y-ethoxypropyl amine.

Cycloaliphatic amines may be, for instance, N-methyl-.

cyclopropylamine, N-methylcyclohexylamine.

Araliphatic amines may be, for instance, phenalkylalkylamines such as N-benzyl-N-methylamine or N-phenethyl-N-methylamine.

Radicals of heterocyclic amines may be, for instance, pyrrolidino, morpholino, thiomorpholino, piperidino, N- methyl-piperazino, N-phenylpiperazino, 4-(fl-hydroxyethyl)-piperazino( l N-(v-hydroxypropyl)-piperazino, hexamethyleneimino radicals,

The 1(2H)-phthalazinone derivatives of the present invention are obtained by acylating, optionally in the presence of an acid-binding agent, l(2H)-phthalazinones of the general formula L3 OH wherein R and R have the meanings given above, and R is either defined as R' above or, where R would contain an acyloxy radical of the general formula c-oll 0 R may represent the radical of the corresponding hydroxy compound in which the acyloxy group is replaced by a hydroxy group, with an alkoxy benzoic acid of the general formula COOH N-orn-omon urn-H31 compound, with a secondary amine of the general formula RH, or

(b) by reacting a 1(2H)-phthalazinone of the general formula with a 'y-halogeno-p-hydroxypropylamine of the general formula HalCH CH(OH)CH R or (c) by cyclizing an ortho-acyl benzoic acid of the general formula COOH with a 'y-amino-fi-hydroxy-propylhydrazine of the general formula In each case, R R R and n are as defined above.

The 1(2H)-phthalazinone derivatives of the present invention are valuable pharmaceuticals. In particular, they are excellent coronary dilators and, in this respect, superior to other known substances of this kind. They may be utilized in pharmaceutical acceptable diluent or carrier.

A pharmacological investigation of the vasodilator action on the coronary vessels, with respect to the change in the oxygen tension in the coronary veinous blood, was.

carried out on dogs according to the methods described by W. K. A. Schaper and his co-workers (see W. K. A. Schaper, R. Xhonneux, and L'M. Bogaa'rd Uber die kontinuierliche Messung des Sauerstotfdruckes im veniisen Coronarblut (Naunyn-Schmiedebergs Arch. exp. Path. 11. Pharmak. 245, 383-389 (1963)). The test preparations were applied intravenously to narcotized and spontaneously breathing animals. Under these test conditions, dilation of the coronary arteries caused by the test substances along with an increase in the coronary blood flow led to an increase in the oxygen tension in the coronary veinous blood. This oxygen tension was measured polarographically by means of a platinum electrode of the Gleichmann- Liibbers type (see U. Gleichmann and D. W. Iluebbers Die Messung des Sauerstoffdruckes in Gasen und Fliissigkeiten mit der Platin-Elektrode unter besonderer Beriicksichtigung de Messung im Blut, Pfliigers Arch. 271, 431-455 (1960)). The heart rate was continuously measured by electronic methods from the systolic peaks of the arterial blood pressure. The arterial blood pressure was measured in the known manner in the femoral artery with the aid of an electromanometer of the Statham strain-gauge type.

The following table gives the results of the pharmacological investigations which were carried out. The preparations were tested in the form of their respective hydrochlorides.

LD o, in the coronary Maximal change in blood pressure gJkg. Dosage, veinous blood in in heart rate in- (systolic/diastolic) inmouse, mg./kg., Preparation 1.v. i.v Percent Minutes Percent Minutes Percent Minutes 2'['y-pyrro1idino-fl-(3,4,5-trimethoxybenzoxy)-propyl1- 5,6,7-trimethoxy1(2H)-phthalazinone 0. 0675 0. 1 +40 90 +39 90 10/-10 +90 Z-I- -diethyIammo-B-(3,4,5-tnmethoxybenzoxy)- ropyl]-5,6,7-t1imethoxy-l(2H)phthalazinone 0. 06 0. 05 +66 20 3/i0 3 2- 'y-(N-methyl-N-methoxypropyl-amino)-B-(3,4,5-

trimethoxybenzoxy)-propy1]-5,6,7-trimethoxy- 1(2H)-n 0. 04 0. 05 +41 +28 25 2-[ -mor holino-B-(3,4,5-trimethoxybenzoxy)- ropyl -5,6,7-trimethoxy-1 (2H) phthalazinone 0. 14 0. 1 +105 25 -4 45 24/15 25 2- y-mor holino-fl-(3,4,5-triethoxy-benzoxy)- ropyl -5,6,7-trimeth0xy-1(2H)-phthalazinone 0. 14 0. 1 +106 35 -21 35 35 2- -y-mor holino--(3,5-diethoxy--n-butoxy-benzoxy)- ropyl -5,6,7-tr1methoxy-1(2H)-phthalazinone 0.115 0. 1 +134 +4 55 -12/26 55 2- 'y-(4-fi-3,4,5-tnmethoxybenzoxyethyl-piperazino[I'D-6-(3,4,5-trlmethoxybenzoxy)-propyl]- 5,6,7trimethoXy-1(2H)-phthalazinone 0. 05 +108 30 +15 30 +8/-6 5 2-['y:(N-methyl-N-eyclohexyl-amino)-fl-(3,4,5-

tnmethoxybenaoxy)-propyl]-5,6,7-t1imethoxy- 1(2H)-phthala zmone 0. 1 0. 05 +43 +39 35 -10/31 2-[ -methylp1peraz1no[1])-fl-(3,4,5-tr1methoxybenzoxy)-propyl]-5,6,7-trimetl1oxy-1(2H)- nh h l m 0. 12 0. 1 +41 10 +7 5 2-i'v-(N-methyl-N-benzyl-amino)-B-(3,4,5-trimeth0xy- 1 benzoxy)-propy1]-5,6,7-trimethoxy-1(2H)- nhthalaflmme 0. 15 0.05 +83 20 -10/5 20 Z-Yy-(perhydro-axe myl-[l])-fl-(3,4,5-trlmethoxybenzoxy)-propy15 5,6,7tzimethoxy-1(2H)- nhihnlnvinnna 0. 1 +37 35 2-l v-piperidino-fl-(3,4,5-trimethoxybenzoxy)- propyl]-,6,7-trimethoxy-1-(2H)-phthalazinone 0. 1 0. 1 55 +22 55 -9/23 55 Comparative substance-3-('y-diethylamino-fihydroxy-propyl)-4 methyl-7-ethoxy-carbonylmethoxy-coumarlne according to French Pat. 5,019 BSM- 2.0 +118 65 e Maximal increase in oxygen tension Maximal change O OH;

O CH; 0 CH;

(a) 37.9 g. (0.1 mol) 2 ('y morpholino-B-hydroxypropyl)-5,6,7-trimethoxy 1(2H) phthalazinone are dissolved in 400 c.c. chloroform and admixed with 11.1 g. (0.11 mol) triethylamine. A solution consisting of 25.3 g. (0.11 mol) 3,4,5 trimethoxybenzoyl chloride in 80 c.c. chloroform is then added dropwise while stirring for 30 minutes at room temperature. Stirring is continued for one hour at room temperature. The reaction mixture is then heated to the boil and stirred again for 8 hours under reflux. After cooling down, it is evaporated to dryness in vacuo. The residue is dissolved with stirring in dilute hydrochloric acid and the solution thus obtained is filtered so as to become limpid. The aqueous hydrochloric acid solution is rendered alkaline by the introduction of solid potassium carbonate and the separating reaction product is dissolved in ethyl acetate. After drying over potassium carbonate, one obtains by introducing gaseous hydrogen chloride into the ethyl acetate solution the 2-[7-morpholino ,9 (3,4,5 trimethoxybenzoxy)-propyl]5,6,7-trimethoxy-1(2H)-phthalazinone hydrochloride in the form of colorless crystals melting at 194-196.

Yield: 48 g. (=78.6% of the theoretical).

(b) The 2 ('y morpholino p hydroxy-propyl)- 5,6,7 trimethoxy 1( 2H phthalazinone required above as a starting compound may be prepared as follows:

23.6 g. (0.1 mol) 5,6,7 trimethoxy 1(2H) phthalazinone are introduced while stirring at room temperature into a solution consisting of 7 g. (0.1 mol) potassium methylate in 120 c.c. methanol. The reaction mixture is evaporated to dryness in vacuo and the remaining potassium salt is suspended in 300 c.c. anhydrous toluene. A solution consisting of 19.8 g. (0.11 mol) N ('y chlorop-hydroxypropyl) morpholine in 40 c.c. anhydrous dimethylsulfoxide is then added dropwise and stirring is continued overnight at 80. After cooling, the reaction mixture is triturated with water and the toluene layeris separated. The toluene phase is extracted several times with dilute hydrochloric acid. The combined hydrochloric acid solutions are filtered till clear and rendered alkaline by the addition of potassium carbonate. The base layer which separates is then dissolved in methylene chloride. The residue obtained after concentrating the methylene chloride is recrystallized from ethyl acetate. 2-(7-morpholino hydroxypropyl) 5,6,7 trimethoxy 1(2H)- phthalazinone is obtained in the form of colorless needles melting at 108-109.

Yield: 30 g. (=79% of the theoretical).

(c) The same intermediate may also be prepared as follows:

24 g. (0.1 mol) 3,4,5 trimethoxy phthalaldehydic acid are suspended in 300 c.c. water and admixed with 17.5 g. (0.1 mol) 'y-morpholino ,8 hydroxypropylhydrazine. The reaction mixture is then heated to boiling point and stirred for 2 hours at 100. After cooling, the

reaction product is filtered olf by suction, washed with water and dried in vacuo.

Yield: 28 g. (=73.8% of the theoretical); m.p.: 108'.

Example 2 OCH; 1* 01130 cmo O/ l-CHCH N OCH; -ocH,

OCH:

Hwm-o-oo 00H,

on, 42.2 g. 0.1 mol) 2 p, 4' p hydroxyethylpipeb azino[l] 8 hydroxy propyl] 5,6,7 trimethoxy- 1 (2H) phthalazinone are dissolved in 300 c.c. anhydrous chloroform and admixed with 30.3 g. (0.3 mol) triethylamine. A solution consisting of 69 g. (0.3 mol) 3,4,5-trime'thoxybenzoyl chloride in 200 c.c. anhydrous chloroform is then added dropwise while stirring at room temperature and stirring is continued for another 2 hours at room temperature. The reaction mixture is then heated to be boiled and stirring is continued for another 10 hours under reflux. After cooling down, the reaction mixture is concentrated in lvacuo and the residue is dissolved in dilute hydrochloric acid and filtered so as to become limpid. The aqueous hydrochloric acid solution is then rendered alkaline by the addition of potassium carbonate and the separating reaction product is dissolved in ethyl acetate. After drying over potassium carbonate one obtains by introducing gaseous hydrogen chloride the 2 [7 (4' )3 3,4,5 trimethoxybenzoxyethyl-piperazino[1']) B (3,4,5 trimethoxy benzoxy) propyl]- 5,6,7 trimethoxy 1(2H) phthalazinone dihydrochloride in the form of colorless needles melting at 190. Yield: 57 g. (=64% of the theoretical).

The 2 (4' p hydroxyethyl piperazino[1']-B- hydroxy propyl] 5,6,7 trimethoxy 1(2I-I) phthalazinone required as starting material may be prepared as follows:

29.2 g. (0.1 mol) 2 (2',3' epoxypropyl) 5,6,7 trimethoxy 1(2H) phthalazinone and 39 g. (0.3 mol) N 18 hydroxyethyl piperazine are dissolved in 250 c.c. alcohol and then stirred for 12 hours under reflux. The limpid reaction solution is freed in vacuo from the solvent and the excess N fl hydroxyethyl piperazine. The residue is recrystallized from ethyl acetate.

2 ['y (4' p hydroxyethyl-piperazino[ 1']-fl-hy droxy propyl] 5,6,7 trimethoxy 1(2H) phthalazinone is obtained in the form of colorless crystals melting at111-112.

Yield: 32 g. (=76% of the theoretical).

(c) The same product is also obtained by reacting 2- (3' chloro 2' hydroxy propyl) 5,6,7 trimethoxy- 1(2H) phthalazinone, prepared by addition of hydrogen chloride to 2 (2',3' epoxy propyl) 5,6,7 trimethoxy- 1(2H)-phthalazinone, with N 8 hydroxyethyl-piperazine, in known manner.

The 2-(2',3'-epoxypropyl) 5,6,7 trimethoxy-1(2H)- phthalazinone required as intermediate is obtained by reacting 5,'6,7-trimethoxy-l(2H)-phthalazinone with epichlorohydrin as follows:

23.6 g. (0.1 mol) 5,6,7 trimethoxy-l(2H)-phthalazinone are dissolved in c.c. dimethylsulfoxide and 11.2

'g. (0.1 'mol) potassium tert. butylat e are added. 'Ihe're'ac- Yield: 21 g. (=72% of the theoretical).

tion mixture is stirred for 2 hours at 30-35 and-admixed i- '1; 1 :25 with 30 g. (0.324 mol) epichlorohydrin. \After 1 2 hours t H 108 stirring at room temperature, it is poured into 800 c.c. water and extracted several times with ethyl acetate. The 5 combined ethyl acetate extracts are washedfirst with 8 a 12g dilute sodium hydroxide solution and then with water. @Hoomh E Hg After drying, the organic phase is concentrated in vacuo; $518833: The residue is recrystallized from petroleum ether. 2-(2', slay-(002ml H 7'5 1:! epoxypropyl)-5,6,7-trimethoXy-l(2H)-phthalaainone g is obtained in the form of colorless crystals melting at 5,6,7-(OCHQ2' H N(CH )CH Csl-I5 Oily spy-(0cm), H

Example 3 5 sea-(0on3), H 120 (a) Starting compounds of the following general fori mula are prepared by methods analogous to those described in paragraphs (b) and (c) of Examples 1 and 2, 5,6,74061191 H 123 (R R and R being as defined in the table:

General formula: 5,6,7 (OC'H3)2. H v 93 5,6,1-(0oHm H- 121 v T. -N N-OH, e

Analogously to the prescription-given in paragraph 1 of OH Examples 1 and 2 the following compounds of the present invention are prepared from the above initial products:

I I v 1 ,i .Q 7 dM-P., I e (no -21. 1 (nos R (1155?? H H .1 3,4,5-(0om); '140 ah 134 3,4,5-(00119; do 1 132 3,4,5-(OCHa): -.d0' 160 3,4,5-(OCHa)a N (CzH5)2 139 3,4,5-(0CHs -N(C2H5)2 92 ,GJ-(O CH8)! 7 -(0 CHa)a ---N (02115): 191 aw-(0cm); v s s-(0cm), f Nwfioomomcmocn, 15s 3 1 4 1); 1 540011): 7 N(C a)C -:CH=CHz 73 5,6,7-(OCH3): v I 3,4,5-(0QH0V v N (CHs)CH2CaH5 92 s,s,7- oom)," a,4,5-(0 om),

- wm) n sea-(00 h ,5-(O9Hih N 139 31617-100111 as cm). 18 0011. 11 3,4,5-EooHi): C) 87 -5',;7- oc11. ass-(pom); r r w V l 13s ,-e,7- 001101 1: 'j'84,5-(OGH I U yr rimv a: 179 g H I. v n

5,6,7-(003 I i 3,5-(QCHah4-OC4H9 Sameasabove. .Q-..

Decomposedr 9 What is claimed is: 1. Basically substituted l(2H)-phthalazinone derivative having the structural formula and their pharmaceutically acceptable acid addition salts,

wherein R stands for a substituent having 2-10 carbon atoms represented by the formula -NR R wherein R is selected from the group consisting of hydrogen, alkyl and benzyl, and R is selected from the group consisting of alkyl, alkenyl, hydroxyalkyl, alkoxyalkyl, dialkylaminoalkyl, cycloalkyl, benzyl and phenethyl,

R stands for a member selected from the group consisting of a hydrogen atom and an alkoxy group having 1-4 carbon atoms, which group may be in the 6,7, 7,8 or 5,6,7 position of the phthalazine nucleus,

R stands for a member selected from the group consisting of hydrogen, methyl and benzyl,

R stands for an alkoxy group having l-4 carbon atoms,

m stands for an integer selected from the group consisting of 1, 2 and 3, and

It stands for an integer selected from the group consisting of 2 and 3.

10 2. Basically substituted 1(2H)-phthalazinone derivative according to Claim 1, wherein R is a substituent selected from the group consisting of diethylamino N-methyl-Nfiymethoxy-propyD-amino, N-methyl-Nbenzylamino, N-

methyl-N-allylamino and N-methyl-N-cyclohexylamino,

and pharmaceutically acceptable acid addition salts thereof.

3. 2- -diethylamino 13 (3,4,5-trimethoxy-benzoxy)- propyl]-5,6,7-trimethoxy-1(2H)-phthalazinone, and pharmaceutically acceptable acid addition salts thereof.

4. 2-['y-(N-methyl-N-cyclohexylamino) B (3,4,5-trimethoxybenzoxy)-propyl] 5,6,7 trimethoxy 1(2H)- phthalazinone, and pharmaceutically acceptable acid addition salts thereof.

5. 2 ['y-N-methyl-N-benZyl-amino) 13 (3,4,5 trimethoxy-benzoxy)-propyl] 5,6,7 trimethoxy 1(2H)- phthalazinone, and pharmaceutically acceptable acid addition salts thereof.

6. 2 ['y-(N-methyl-N-methoxypropyl-arnino)- 3-(3,4,5- trimethoXybenz0xy)-propyl] 5,6,7 trirnethoxy-1(2H)- phthalazinone and pharmaceutically acceptable acid addition salts thereof.

References Cited UNITED STATES PATENTS 3,017,411 l/ 1962 Engelbrecht et al. 26()247.2 3,433,641 3/1969 Margot 99-2 3,539,567 11/1970 Doebel ct al 260-250 G. THOMAS TODD, Primary Examiner US. Cl. X.R.

260-243 B, 247.2 A, 247.2 B; 424246, 248, 250 

1. BASICALLY SUBSTITUTED 1(2H)-PHTHALAZINONE DERIVATIVE HAVING THE STRUCTURAL FORMULA 